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Discussion Starter · #1 ·
-Warning: long post incoming-

Hello there! First of all excuse me if this post doesn't belong here. This is my first (finally!) post with videos and pictures of my recently adquired Torque Slingshot. My dad and I watch mostly every Joerg's video when I come home from university and that made us get some rubber and make a slingshot in the old way (it broke after some shots but we could know that we needed something better). .

After waiting two weeks, it finally arrived.

I made a band set of TBG (two layers per side: 21cm long - 2,4cm fork - 1,1cm pouch) with a rotary cutter that I bought on Amazon (now i have to buy the cutting map so the blades last longer) and made the pouch from some leather of an old shoe (it's way thicker than the normal pouch I'm used to see, but it works for now). Also, I tied the pouch with some kite string we had at home (we tied it with bands on the homemade slingshot we made at first, now we did it this way to make it lighter). I took the sizes from the calculator (about 95cm of draw length, 9 lvl stretch and about 7 tapering using 12mm steel balls) but I kinda rounded the numbers :p. May I say that they were a bit bigger in all ways compared to the ones I made for the homemade one.

We went to my grandma's house and grabbed an old tv that doesn't work more and took care of it :D (also spreading some pellets to a famous drink brand)

[youtube]a6AFdbzGw1k[/youtube]

Also we have been shooting to some wood we had, pretty nice results.




The thing is that after about 50 shots more or less one band started to rip and few more shots later it broke. After making a replacement and shooting another 30 shots, the first pouch broke and another band broke too. I made entirely a new set with the same measures and it's working well (I know the pouch is ugly and bad as hell but it's the leather we could get on a sunday afternoon):


The ammo:


but after 20 shots +- it looks like this:


My question is, maybe making the band longer both in the pouch and fork part (about 1cm) and making less tapering on it will make the band last longer?

Also, can anyone tell me some measures for a band set (double layered if possible) that can perform more or less like the one I made but that will last longer?

Thanks for your time and I hope you liked the post!
 

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Welcome and thanks for the fun video and pictures.

As for your problem - that band set has a very steep taper. You may wish to increase the pouch end to about 2.0 cm width. Also, reduce the size of your pouch so it barely fits around the ammo. The large pouch causes "whiplash" that hyper extends the bands once the ammo departs. Last, those bands are a little strong for the ammo size/weight. This also causes the same "whiplash" effect since only a portion of the power is transferred to the ammo.

What you have will give you incredible speed and power with a reasonably easy pull. However, this also causes the bands to wear out really quickly. The band failure rate you are getting is not surprising given your setup. Understand, once you make the changes above, you will lose some power and speed or have to pull harder to obtain the same results. But, the bands will last longer.
 

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Discussion Starter · #3 ·
Welcome and thanks for the fun video and pictures.

As for your problem - that band set has a very steep taper. You may wish to increase the pouch end to about 2.0 cm width. Also, reduce the size of your pouch so it barely fits around the ammo. The large pouch causes "whiplash" that hyper extends the bands once the ammo departs. Last, those bands are a little strong for the ammo size/weight. This also causes the same "whiplash" effect since only a portion of the power is transferred to the ammo.

What you have will give you incredible speed and power with a reasonably easy pull. However, this also causes the bands to wear out really quickly. The band failure rate you are getting is not surprising given your setup. Understand, once you make the changes above, you will lose some power and speed or have to pull harder to obtain the same results. But, the bands will last longer.
The next set I will make will be wider on the pouch end as you say, and I will also use a smaller pouch.

About the bands, as I said I got the measurements from the calculator using a 12mm steel ball.

Can you tell me the sizes for a good band set even if I have to pull harder? Thanks for your response.
 

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A taper of roughly 0.5 cm over 20 to 24 cm length is adequate for safety and gives decent speed. For 1 cm ammo, your pouch should be about 1 cm tall and 4 cm long. One layer of 2 cm width at the fork should be more than adequate for up to 1 cm steel ammo.
 

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Discussion Starter · #5 ·
A taper of roughly 0.5 cm over 20 to 24 cm length is adequate for safety and gives decent speed. For 1 cm ammo, your pouch should be about 1 cm tall and 4 cm long. One layer of 2 cm width at the fork should be more than adequate for up to 1 cm steel ammo.
So about 2cm on the fork and 1.6cm on the pouch in 22cm long for 12mm steel balls will be enough? Only one layer sounds not really powerful but I will give it a try. Thanks for your help.
 

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So about 2cm on the fork and 1.6cm on the pouch in 22cm long for 12mm steel balls will be enough? Only one layer sounds not really powerful but I will give it a try. Thanks for your help.
You want about 400% extensension at full butterfly for best band performance. 22 cm will give you about 90 cm at full extension.
 

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Discussion Starter · #7 ·
You want about 400% extensension at full butterfly for best band performance. 22 cm will give you about 90 cm at full extension.
That sounds interesting, I measured my draw length from my extended arm to my face (the normal shooting way I think). I will measure it again in butterfly and make the calculation again.

How do you know when you reach the 400% extension?
 

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You only know by calculation. Theraband will stretch to about 550% max and you will feel it stop when you get to that point. However, pulling to that max will quickly wear out your bands.
 

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Discussion Starter · #10 ·
You only know by calculation. Theraband will stretch to about 550% max and you will feel it stop when you get to that point. However, pulling to that max will quickly wear out your bands.
Yeah, I realised later about that haha, I will make my own calculations about that and see what comes out.
 

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you must find a tradeoff between power and rubber life ... seems to me double bands are too much for !/2" steel, doubles or triple TBG are good for really heavy ammo as Jörg usually shoots ...
Arturo
 
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